South Africa have called up uncapped former Sharks lock Gerhard Mostert following a succession of injuries to their second rows.

The 26-year-old will join up with the squad in Sydney on Sunday as a replacement for Johann Muller, who has failed to recover from a hamstring strain and will return to South Africa.

The Springboks, who lost their opening Tri-Nations clash to Australia on Saturday, are also without injured locks Victor Matfield, Bakkies Botha and Andries Bekker while Flip van der Merve suffered a rib cartilage injury in the 39-20 defeat to the Wallabies in Sydney.

Mostert was part of the team's pre-tour camp as a precaution before leaving for Paris where he has signed for Stade Francais from the Sharks.